KR20100125805A - Heat-dissipating substrate and fabricating method of the same - Google Patents

Abstract

PURPOSE: A heat dissipating substrate and a manufacturing method thereof are provided to form a circuit layer by forming an anode oxidation insulating layer in a metal core. CONSTITUTION: A first core substrate(112a) is formed by laminating a first circuit layer(110a) on a first metal core(102a) which has a first anode oxidation insulating layer(108a). A second core substrate(112b) is electrically connected to the first core substrate. The second core substrate is formed by laminating a second circuit layer(110b) on a second metal core(102b) which has a second anode oxidation insulating layer(108b). A front layer penetration hole is formed by eliminating an insulating member(114) between a first penetration hole and a second penetration hole. A conductive material(120) is inserted into the front layer penetration hole.

Description

Heat dissipation substrate and its manufacturing method {HEAT-DISSIPATING SUBSTRATE AND FABRICATING METHOD OF THE SAME}

The present invention relates to a heat dissipation substrate having improved heat dissipation performance and a method of manufacturing the same.

In general, a printed circuit board is wired to one side or both sides of a board made of various thermosetting synthetic resins, and then ICs and electronic components are disposed and fixed on the boards, and electrical wiring therebetween is coated with an insulator.

One of the most problematic areas when configuring an electronic circuit using an IC or an electronic component on such a printed circuit board is a countermeasure against heat of a component in which heat is generated. That is, when a predetermined voltage is applied to the electronic component, a current flows, which inevitably generates heat due to resistance loss. At this time, there are some electronic parts that do not interfere with operation due to natural air cooling due to the low heat generation.However, in the case of heat generating parts in which the temperature of the electronic parts continuously rises due to the high heat generation, there is a limit to the natural air cooling alone. And breakage is sometimes a problem, such heat generation causes a problem in the reliability of the entire electronics.

In order to solve this problem, various structures for heat dissipation and cooling have been proposed. For example, Korean Utility Model Publication No. 20-1991-0005748 discloses a printed circuit board having a heat sink.

However, this requires a separate additional structure for heat dissipation, so there is a problem in that it cannot adequately cope with the slim / miniaturization trend of various electronic products. Moreover, since the additional structure is included, there is a problem that the unit cost of the product rises and causes a failure.

Therefore, a method of improving heat dissipation efficiency by inserting a metal having high thermal conductivity into a printed circuit board instead of adding an additional structure to increase heat dissipation efficiency without such a problem has been proposed.

1 to 6 illustrate a conventional manufacturing process of a multilayer printed circuit board having such a heat dissipating metal, and the manufacturing process thereof will be described with reference to the following.

First, as shown in FIG. 1, the through-hole 2 is processed to the metal core 1 with high thermal conductivity using a CNC drill.

Next, as shown in FIG. 2, the insulating material 3 and the copper foil layer 4 are laminated on the metal core 1.

Next, as shown in FIG. 3, via holes 5 are formed in the through-holes 2 of the metal core 1 through mechanical processing for interlayer connection. Here, the via hole 5 should be processed to a size smaller than the through hole 2 of the metal core 1 in order to insulate the copper plating layer of the inner wall of the via hole 5 by copper plating.

Next, as shown in FIG. 4, a copper plating layer is formed on the inner wall of the via hole 5 so as to be interlayer connected by chemical copper plating, that is, an electroless copper plating process and an electrolytic copper plating process, and an inner circuit pattern by exposure, development, and etching. (6) is formed.

Next, as shown in FIG. 5, the insulating layers 7a and 7b and the circuit layer 8 are formed by a general build-up method to form outer layers as many as desired layers.

Finally, as shown in Fig. 6, in order to protect the outer surface protection and insulation, a solder resist layer 9 having an open portion is formed on the outer layer surface to manufacture a multilayer printed circuit board.

The conventional multilayer printed circuit board improves heat dissipation efficiency by inserting a metal core having excellent thermal conductivity into an inner layer core.

However, the conventional multilayer printed circuit board attempts to dissipate heat by inserting a metal core 1 therein, but only one metal core 1 has a limitation in dissipating heat generated from the multilayer printed circuit board.

The present invention has been made to solve the above problems, an object of the present invention is to provide a heat dissipation substrate with improved heat dissipation performance and a method of manufacturing the same.

According to a preferred embodiment of the present invention, a heat radiating substrate may include an insulating member, an inner wall of a first via hole and a first through hole attached to an upper portion of the insulating member, on a first metal core having a first anodized insulating film formed on a surface thereof. A second anodization insulating layer formed on a surface of the first core substrate having a first circuit layer and an inner wall of the second via hole and the second through hole attached to a lower portion of the insulating member, the first core substrate being electrically connected to the first core substrate; And a second core substrate having a second circuit layer formed on the formed second metal core.

Here, the insulating member between the first through hole and the second through hole is removed to form a full layer through hole connected to the first through hole and the second through hole, wherein the full layer through hole is a conductive material. The intervening circuit is characterized in that the first circuit layer of the first core substrate and the second circuit layer of the second core substrate are electrically connected.

In addition, the conductive material is a plating layer formed on the inner wall or the inside of the full-layer through-holes or characterized in that the conductive paste.

In addition, the metal core is characterized in that the aluminum or aluminum alloy.

In addition, the anodization insulating film is characterized in that the aluminum anodization film (Al ₂ O ₃ ).

In the method of manufacturing a heat dissipation substrate according to a preferred embodiment of the present invention, (A) a first circuit layer is formed on a first metal core including a first via hole and an inner wall of a first through hole, on which a first anodization insulating film is formed; Manufacturing a first core substrate, (B) manufacturing a second core substrate having a second circuit layer formed on a second metal core having a second anodization insulating film formed on a surface thereof including an inner wall of a second via hole and a second through hole; (C) arranging the first core substrate and the second core substrate so that the first through hole and the second through hole coincide with each other up and down, and then using the insulating member to form the first core substrate and the second core substrate. Attaching the two core substrates, (D) removing the insulating member filled in the first through hole and the second through hole, and removing the insulating member between the first through hole and the second through hole. Forming a full layer through hole, and (E) the And connecting the first circuit layer of the first core substrate and the second circuit layer of the second core substrate by plating or filling a conductive material in the entire layer through hole.

At this time, the metal core is characterized in that the aluminum or aluminum alloy.

In addition, the anodization insulating film is characterized in that the aluminum anodization film (Al ₂ O ₃ ).

The features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings.

Prior to this, terms and words used in the present specification and claims should not be construed in a conventional and dictionary sense, and the inventor may appropriately define the concept of a term in order to best describe its invention The present invention should be construed in accordance with the spirit and scope of the present invention.

According to the present invention, a four-layer heat dissipation substrate is manufactured by stacking a core substrate having a two-layer structure including a metal core, and the heat dissipation performance is improved by including two metal cores in the four-layer structure.

In addition, according to the present invention, by forming an anodized insulating film on the metal core to form a circuit layer, the heat dissipation performance is improved by an anodizing insulating film having a higher thermal conductivity than a general insulating material while reducing the thickness of the heat radiating substrate.

The objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and the preferred embodiments associated with the accompanying drawings. In the present specification, in adding reference numerals to the components of each drawing, it should be noted that the same components as possible, even if displayed on different drawings have the same number as possible. In addition, in describing the present invention, when it is determined that the detailed description of the related known technology may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

 Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Heat sink board structure

7 is a cross-sectional view of a heat radiation board according to a preferred embodiment of the present invention. Hereinafter, the heat dissipation substrate 100 according to the present embodiment will be described with reference to this.

As shown in FIG. 7, the heat dissipation substrate 100 according to the present exemplary embodiment has a structure in which two core substrates 112a and 112b having a metal core are stacked with the insulating member 114 interposed therebetween.

The core substrates 112a and 112b may be formed on the first metal core 102a including the first via hole 104a and the inner wall of the first through hole 106a and having the first anodized insulating film 108a formed thereon. The first core substrate 112a having the first circuit layer 110a and the second core hole 112b electrically connected to the first core substrate 112a and attached to the lower portion of the insulating member 114, and the second through The second core substrate 112b includes the second circuit layer 110b formed on the second metal core 102b including the inner wall of the hole 106b and the second anodized insulating film 108b formed on the surface thereof.

At this time, the first core substrate 112a and the second core substrate 112b remove the insulating member 114 between the first through hole 106a and the second through hole 106b to remove the first through hole 106a. And a full-layer through-hole 118 connected to the second through-hole 106b, and the full-layer through-hole 118 is electrically connected to each other by interposing the conductive material 120. Here, the conductive material 120 may be a plating layer formed on the inner wall or the inside of the full-wall through hole 118 or may be a conductive paste.

In addition, the first metal core 102a and the second metal core 102b are easily available at a relatively low cost, have excellent heat transfer properties, and are made of an anodizable metal, for example, aluminum. (Al) or aluminum alloy can be used.

In addition, the first anodized insulating film 108a and the second anodized insulating film 108b include, for example, an aluminum anodized insulating film (Al ₂ O ₃ ) having a relatively high heat transfer property of about 10 to 30 W / mK. It is preferred to be used.

Manufacturing method of heat radiation board

8 to 15 are process cross-sectional views illustrating a method of manufacturing a heat dissipation substrate according to a preferred embodiment of the present invention in order of process. In the method for manufacturing a heat dissipation substrate according to the present invention, two core substrates having a two-layer structure in which anodized insulating film is formed on a metal core are manufactured, and two metal cores are connected by attaching two core substrates through an insulating member and then connecting them. It is characterized by manufacturing a heat radiation board having a four-layer structure provided. Although the following description focuses on manufacturing a four-layer heat dissipation substrate, it will be obvious that a heat dissipation substrate having a multi-layer structure such as six layers and eight layers can be manufactured by the same principle. Hereinafter, a method of manufacturing the heat radiation board according to the present embodiment will be described in detail with reference to FIGS. 8 to 15.

First, as shown in FIG. 8, the first via hole 104a and the first through hole 106a are formed in the first metal core 102a.

Here, the first via hole 104a is for connecting the interlayer circuit layer of the first core substrate 112a, and the first through hole 106a is for interlayer between the first core substrate 112a and the second core substrate 112b. It is for connection.

The first via hole 104a and the first through hole 106a are processed by a mechanical drilling or laser (eg, a CO 2 laser, a Yag laser) such as a Computer Numerial Control drill.

In this case, the first metal core 102a to be used is easily available at a relatively low cost, has excellent heat transfer characteristics, and is made of an anodizable metal, for example, aluminum (Al) or an aluminum alloy. This can be used.

Next, as shown in FIG. 9, the first anodization insulating film 108a is formed on the entire surface of the first metal core 102a.

Here, the first anodization insulating film 108a is formed by an anodizing process. Specifically, the first anodization insulating film 108a contains the first metal core 102a in an electrolyte such as boric acid, phosphoric acid, sulfuric acid, and chromic acid, and then applies an anode to the first metal core 102a, and applies a cathode to the electrolyte. It is formed by applying.

In this case, the first anodization insulating film 108a is preferably an aluminum anodization insulating film (Al ₂ O ₃ ) having a relatively high heat transfer property of, for example, about 10 to 30 W / mK.

In the present invention, the thickness of the heat dissipation substrate can be reduced and heat dissipation efficiency can be achieved by adopting the first anodization insulating film 108a which is thinner than the conventional insulating layer and has excellent heat transfer characteristics.

Next, as shown in FIG. 10, a plating layer is formed on the first metal core 102a on which the first anodization insulating film 108a is formed by a plating process (electroless copper plating process and electrolytic copper plating process), and then patterning process. Is performed to form the first circuit layer 110a. As a result, the first core substrate 112a is manufactured.

At this time, the first circuit layer 110a may, for example, laminate a dry film on the plating layer, form an open portion in the dry film by an exposure and development process, and then remove the plating layer exposed by the open portion by etching. Is formed.

Next, as illustrated in FIG. 11, the second metal core 102b including the inner walls of the second via hole 104b and the second through hole 106b has a second anodized insulating film 108b formed thereon. The second core substrate 112b on which the second circuit layer 110b is formed is manufactured.

In this case, since the second core substrate 112b may be manufactured in the same manner as the method of forming the first core substrate 112a shown in FIGS. 8 to 10, the description thereof will be omitted.

Next, as shown in FIG. 12, the first through hole 106a of the first core board 112a and the second through hole 106b of the second core board 112b with the insulating member 114 interposed therebetween. After the upper and lower sides are disposed so as to coincide with each other, the first core substrate 112a and the second core substrate 112b are attached by pressing.

At this time, when the first core substrate 112a and the second core substrate 112b are pressed, the insulating member 114 in the semi-cured state is formed in the first and second via holes of the first and second core substrates 112a and 112b. It is inserted and filled into the 104a, 104b and the first and second through holes 106a, 106b. In particular, since the insulating member 114 inserted and filled in the first and second via holes 104a and 104b may serve as plugging ink, the insulating member 114 may be inserted into the first and second via holes 104a and 104b in a subsequent process. There is no need to fill additional fillers for improved reliability. However, when the insulating member 114 is not completely filled in the first and second via holes 104a and 104b, additional plugging ink may be filled in a subsequent process.

Next, as shown in FIG. 13, the first through hole 106a and the second through hole 106b including the insulating member 114 filled in the first through hole 106a and the second through hole 106b. Remove the insulating member 114 present in the).

Here, the insulating member 114 can be removed by a drilling operation or the like, and the full-layer through-hole 118 penetrating the first through-hole 106a and the second through-hole 106b as a whole is formed by this step.

Meanwhile, hereinafter, the through-hole region formed by removing the insulating member 114 between the first through hole 106a and the second through hole 106b from the entire through hole 118 for the convenience of description will be described as a third through hole. Referred to as (116).

Next, as shown in FIG. 14, the first circuit layer of the first core substrate 112a may be plated or filled with a conductive material 120 such as a plating layer or a conductive paste on the inner wall or the inside of the full-layer through hole 118. 110a and the second circuit layer 110b of the second core substrate 112b are connected to each other.

For example, the conductive material 120 is formed on the inner wall of the full-layer through-hole 118 by a sputtering process to form the first circuit layer 110a and the second core substrate 112b of the first core substrate 112a. Two circuit layers 110b may be connected.

However, the method shown in FIG. 14 is just one example, and various methods such as forming a full-layer through via in the full-layer through-hole 118 or filling a conductive paste therein may be applied by performing a plating process. It will be understood that this will also be included within the scope of the invention. In this case, the plugging ink 122 may be injected into the entire layer through hole 118.

Finally, as shown in FIG. 15, the pads are formed on the second circuit layer 110b formed on the outer layers of the first core layer 112a and the second core substrate 112b formed on the outer layer of the first core substrate 112a. A solder resist layer 124 having an open portion exposing portions is formed.

By this manufacturing process, the heat radiation substrate 100 having a four-layer structure having two metal cores 102a and 102b is manufactured.

Although the present invention has been described in detail through specific embodiments, this is for explaining the present invention in detail, and the heat dissipation substrate and its manufacturing method according to the present invention are not limited thereto, and the technical features of the present invention It will be apparent that modifications and improvements are possible by those skilled in the art.

All simple modifications and variations of the present invention fall within the scope of the present invention, and the specific scope of protection of the present invention will be apparent from the appended claims.

1 to 6 are process cross-sectional views showing a conventional manufacturing method of a multilayer printed circuit board having a heat-radiating metal in the order of process.

7 is a cross-sectional view of a heat radiation board according to a preferred embodiment of the present invention.

8 to 15 are process cross-sectional views illustrating a method of manufacturing a heat dissipation substrate according to a preferred embodiment of the present invention in order of process.

<Description of the symbols for the main parts of the drawings>

102a and 102b: Metal core 104a and 104b: Via hole

106a, 106b: Through hole 108a, 108b: Anodized insulating film

110a, 110b: circuit layer 112a, 112b: core substrate

114: insulating member 116: third through hole

118: all-layer through hole 120: conductive material

Claims (8)

Insulation member; A first core substrate having a first circuit layer formed on a first metal core having a first anodization insulating film formed on a surface thereof, including an inner wall of a first via hole and a first through hole attached to an upper portion of the insulating member; And A second circuit layer is formed on a second metal core electrically connected to the first core substrate, the second metal core having a second anodization insulating layer formed on a surface thereof, including an inner wall of a second via hole and a second through hole attached to a lower portion of the insulating member. Formed second core substrate Heat dissipation substrate comprising a. The method according to claim 1, The insulating member between the first through hole and the second through hole is removed to form a full-layer through hole connected to the first through hole and the second through hole, And the conductive layer is interposed between the first layer through hole and the first circuit layer of the first core substrate and the second circuit layer of the second core substrate are electrically connected to each other. The method according to claim 2, And the conductive material is a plating layer formed on the inner wall or inside of the full-layer through hole or a conductive paste. The method according to claim 1, The metal core is a heat sink, characterized in that the aluminum or aluminum alloy. The method according to claim 1, The anodization insulating film is a heat dissipation substrate, characterized in that the aluminum anodized film (Al ₂ O ₃ ). (A) manufacturing a first core substrate including a first via hole and an inner wall of the first through hole, the first core substrate having a first circuit layer formed on a first metal core having a first anodization insulating film formed on a surface thereof; (B) manufacturing a second core substrate including a second via hole and an inner wall of the second through hole, the second core substrate having a second circuit layer formed on a second metal core having a second anodization insulating film formed on a surface thereof; (C) After disposing the first core substrate and the second core substrate so that the first through hole and the second through hole coincide with each other, the first core substrate and the second core substrate using an insulating member. Attaching; (D) removing the insulating member filled in the first through hole and the second through hole, and removing the insulating member between the first through hole and the second through hole to form a full layer through hole; ; And (E) connecting the first circuit layer of the first core substrate and the second circuit layer of the second core substrate by plating or filling a conductive material in the entire layer through hole. Method of manufacturing a heat radiation board comprising a. The method according to claim 6, The metal core is a manufacturing method of the heat-radiating substrate, characterized in that the aluminum or aluminum alloy. The method according to claim 6, The anodization insulating film is a method of manufacturing a heat sink substrate, characterized in that the aluminum anodized film (Al ₂ O ₃ ).

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